#4 Rusev

A two-time WWE United States Champion, Rusev is the only Bulgarian to have wrestled for WWE. He made his WWE main roster debut at the 2014 Royal Rumble match where he was eliminated by four men.
Following his debut, "The Bulgarian Brute" was dominant and destroyed every Superstar that came along his path. His first loss came a year later at Wrestlemania 31, when he dropped the United States title to John Cena.
John Cena's last PPV's name revealed by Kurt Angle? More details HERE
Most recently, Rusev has been on a losing streak and this could just be the spark for a feud with the SmackDown Commissioner. Furthermore, his omission from Team SmackDown which is set to face Team Raw at Survivor Series should ignite this feud.
Expect him to vent his frustrations to Shane and complain about not getting enough opportunities that he believes he deserves.
A brutal attack on Shane would most likely happen sometime after the Royal Rumble to set up a match at Wrestlemania 34. This might just be the way to get Rusev over once again.